Breakout wrench

ABSTRACT

A breakout wrench for drilling apparatus includes a pivotably mounted slide arm upon which a carriage is slidably mounted and a set of wrench jaws which are attached to a wrench arm swingably disposed upon the carriage for engaging and loosening a drill string section of the drilling apparatus. A hydraulic cylinder associated with and disposed beneath the slide arm is attached to the carriage to provide movement of the carriage along the slide arm and impart a wrenching movement to a drill string section through the accompanying wrench arm. A stop pin is provided to secure the slide arm in a stored position during normal drilling operations.

. United States Patent 1191 Lang et a1. Sept. 3, 1974 BREAKOUT WRENCH3,288,000 11/1966 Foster 81/57.34 [75] Inventors: David Lang, southMilwaukee; 3,500,708 3 1970 Wilson 111 5733 Jack D. Nelmark, New Berlin;Matthew Smith, Milwaukee, all of Wis.

Primary Examiner-James L, Jones, Jr. Attorney, Agent, or Firm-Quarles &Brady [5 7 ABSTRACT A breakout wrench for drilling apparatus includes apivotably mounted slide arm upon which a carriage is slidably mountedand a set of wrench jaws which are attached to a wrench arm swingablydisposed upon the carriage for engaging and loosening a drill stringsection of the drilling apparatus. A hydraulic cylinder as sociated withand disposed beneath the slide arm is attached to the carriage toprovide movement of the carriage along the slide arm and impart awrenching movement to a drill string section through the accompanyingwrench arm. A stop pin is provided to secure the slide arm in a storedposition during normal drilling operations.

7 Claims, 6 Drawing Figures PATENTEDSEP 14 3.832.918 sum 20! 3 PATENTED3974 I SHEET 3 0F 3 BREAKOUT WRENCH BACKGROUND OF THE INVENTION Theinvention relates to rotary drilling apparatus and more particularly toa breakout wrench used to loosen and disconnect sections of a drillstring. The preferred embodiment is especially useful in the disjointingof pipe sections in a rotary blast hole drill, but the invention is notlimited exclusively to this application and may be utilized whereever itis desirable to withdraw pipe sections in drilling apparatus.

In typical blast hole drilling operations, it is customary procedure todrive a drill string formed by several joined sections of drill pipe,each having a typical length of 60 feet, into the earth forming a deep,elongated hole within which a blast or dynamite charge may be insertedsubsequent to withdrawal of the drilling apparatus. During suchwithdrawal, it is necessary to employ a breakout wrench for uncouplingindividual pipe sections of the drill string from themselves and fromthe rotary head mechanism. The disconnecting of the threaded pipe jointsin the string is actually effected by gripping tongs or jaws whichengage and rotate an upper pipe section while the next lower section isheld against rotation by an associated tool wrench or backup tong. Sincethe drill pipe sections are extremely heavy and cumbersome, it isdesirable to provide a breakout wrench which will safely and quicklyfacilitate a loosening of the joints and require a minimum of manualhandling.

Conventional breakout wrenches are known to those in the art as ByronJackson casing tongs comprising a large size wrenching mechanism whichmust be lifted into place about a pipe section by means of a suspensioncable and fixedly pinned by hand at one end. Such a casing tong furtherincludes jaws atthe other end which are manually disposed and lockedabout the periphery of the drill pipe, the jaws being actuated torotatably breakout a pipe joint by retracting a hydraulic cylinderconnected to the wrenching mechanism. Utilization of these wrenchingappliances provides an eccentric rotation about the drill pipe due toits fixed end construction and necessitates a great deal of skillfulmanipulation in order toeffectively break a pipe joint.

SUMMARY OF THE INVENTION The present invention provides a breakoutwrench for drilling apparatus having a pivotably mounted slide arm, acarriage slidably mounted upon the'slide arm, a

hydraulic actuator connected intermediate the carriage and slide arm, awrench arm pivotably affixed to the carriage and a set of wrench jawsjoined to the outer end of the wrench arm. The slide arm swings in ahorizontal plane towards and away from a drill string and the hydraulicactuator causes the carriage to move axially back and forth along theslide arm whereupon the accompanying wrench arm and wrench jaws arepivotable to positively engage and rotate a length of drill pipe.

It is a general objective of the invention to provide a breakout wrenchwhich will loosen pipe joints between successive sections of drill pipeand between the rotary head mechanism and a drill pipe section quicklyand effectively with a minimum of manual effort. This is accomplished byemploying a construction which furnishes threefold movement of thecomponents to insure that a centralized rotation of the drill pipe isattained. A single hydraulic cylinder allows for an efficientpositioning of the wrench jaws about the pipe when in a relaxed positionand serves to impart a positive uncoupling of the drill pipe duringextension. This feature especially provides for a substantial reductionin cost and weight of the entire device and ofiers a breakoutarrangement not only fimctionally preferable but economicallyattractive.

Another objective of the invention is to provide a breakout wrench whicheliminates the need for manually connecting a cable to the wrench unitand subsequently pinning a hydraulic cylinder to the wrench. Bypivotably mounting the slide arm to the drilling apparatus and disposinga hydraulic cylinder beneath the slide arm for pivotal movement with it,the only manual task entailed is for a single man to lock the wrenchjaws about the pipe. As a result, not only is the amount of manual laborsignificantly decreased but also the margin of safety in handling istremendously improved.

The foregoing and other objects and advantages of the invention willappear from the following description. In the description, reference ismade to the accompanying drawings, which form a part hereof, and inwhich there is shown by way of illustration and not of limitation apreferred embodiment of the invention.

Such embodiment does not represent the full scope of the invention, butrather the invention may be employed in many different embodiments, andreference is made to the claims herein for interpreting the breadth ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation of arotary blast hole drill incorporating the breakout wrench of the presentinvention;

FIG. 2 is a top view of the breakout wrench, as mounted in FIG. 1,showing the hydraulic actuating cylinder in retracted position andillustrating the manner in which the wrench jaws engage a drill pipesection;

FIG. 3 is a topview of the breakout wrench, similar to FIG. 2, showingthe slide arm swung away from the mast upright and the hydraulicactuating cylinder in a fully extended position;

FIG. 4 is a side view in elevation of the breakout wrench of FIG. 2taken on the plane 4-4;

FIG. 5 is a fragmentary view in cross section of the slide arm, wrencharm and carriage of FIG. 4 taken on the plane 5--5; and

FIG. 6 is a viewin cross section of the breakout wrench of FIG. 4 takenon plane 6- 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a rotaryblast hole drill, generally designated by the reference numeral 1,includes a tiltable mast 2 pivotably movable between a horizontaltransporting position and a series of variable, raised drillingpositions, one of which is vertical as illustrated. A number of drillpipe sections 3 are joined together by threaded pipe joints 4 and thedrill string thus formed is driven downwardly into the earth by means ofa rotary head driving mechanism 5 which runs longitudinally along themast 2. Since a blast hole drill of the character above outlined is wellknown and does not per se comprise substance of the present inventionfurther description thereof is unnecessary. While the invention issuitable for such drills, however, it should be understood that it isapplicable to any oil, gas or water drilling rig as well as any otherequipment which necessitates uncoupling of drill pipe sections.

As shown best in FIGS. 2-4, the improved breakout wrench, generallydesignated by the reference numeral 6, has a slide arm 7 mounted at itsinner end on a pivot hinge 8 for swinging movement towards and away fromthe drill pipe 3. The hinge 8 is preferably secured to a supportingframe 9, but may be located at any desirable point upon the drillingapparatus 1. The slide arm 7 comprises an elongate, cantilevered boxbeam 10 having a flat guide rail 1 l welded, or otherwise affixed, tothe underside of the outer portion of the beam 10. The box beam 10 isalso formed at its inner end with a vertical, keyshaped opening 12. Atubular sleeve 13 and a downwardly projecting reaction plate 14 areinserted through the opening 12, and the sleeve 13, plate 14 and beam 10are welded together to form a unitary whole. The sleeve 13 forms amounting post for the slide arm 7 that is disposed between andvertically aligned with apertures 15 of two parallel, spaced apart andhorizontally disposed support plates 16 of the pivot hinge 8. A drop pin17, that is a part of the hinge 8, is inserted through the apertures 15and the sleeve 13, with its lower end resting upon the topside of atransverse crossbeam 18 to serve as the axis about which the slide arm 7pivots.

A carriage I9 is slidably mounted upon and hangs beneath the guide rail11. This carriage 19 has a flat base plate 20 on which a pair of spaced,parallel slides 21 are mounted that extend upwardly and turn over theside margins of the guide rail 11. The slides 21 thus define a trackwaywithin which the guide rail 11 fits to form the slide mounting for thecarriage 19. As viewed in FIG. 5, the left hand slide 21 includes ashallow levelling strip 22 which functions to cant the base plate 20 ata slight angle, for a purpose to be hereinafter described. v

Disposed immediately beneath and fixed to the base plate 20 is a spindle23 that is an integral part of the carriage .19. The spindle 23 includesa bearing collar 24, and resting upon the collar 24 is a socket end 25of a wrench arm 26. The-socket end 25 is annular, surrounds the spindle23, and is held captive by the carriage 19 to provide a pivoted mountingfor the wrench arm 26. An elongate shank portion 27 of the wrench arm 26extends horizontally in cantilever fashion from the socket end 25 andterminates in a curved outer end portion 28. Pivotably attached to theouter end portion 28 is a set of wrench jaws 29 similar, or like, thoseof a Byron Jackson casing tong. The wrench arm 26 is positioned in asubstantially horizontal plane, and to facilitate this orientation thelevelling strip 22 is provided which cants the carriage 19 to counteractfor the looseness of the assembled parts and'the mass of the wrench arm26, which combine to slightly depress the wrench arm 26 from the axis ofthe spindle 23.

Turning now to FIGS. 4 and 6, a double-acting hydraulic cylinder 30 islocated beneath the box beam 10 of the slide arm 7 for pivotal movementtherewith. The casing end 31 of the cylinder 30 is pinned to the lowerend of the reaction plate 14, and the rod end 32 is pinned to theunderside of the carriage spindle 23. As a result of these connections,actuation of the hydraulic cylinder 30 causes the carriage 19 to moveback and forth along the longitudinal axis of the slide arm 7.

In order to prevent the breakout wrench 6 from interfering with a drillstring during normal drilling operations, means are provided to securethe slide arm 7 adjacent an upright of the mast 2. Specifically, withreference to FIGS. 2, 4 and 6, a horizontal bar 33 is secured to themast upright and projects toward the mast center in parallelrelationship with the mast crossbeam 18. When the slide arm 7 is pivotedclockwise, as viewed from above in FIG. 2, the bar 33 is beneath theslide arm 7 and above the hydraulic cylinder 30. The bar 33, then servesas a rest for the slide arm 7 and its end extends beyond the bottom ofthe beam 10, to present a vertical bore 34. A removable stop pin 35 witha head 36 is inserted in the bore 34, and the head 36 acts as a stopholding the slide arm 7 from swinging toward the drill string. Thewrench arm 26 may be swung outward to the outboard side of the mast 2,where it will not obstruct rotary drilling operations.

To operate the breakout wrench 6, the wrench arm 26 is swung into theposition shown in FIG. 2, and the wrench jaws 29 are locked about theperiphery of the drill pipe section 3 above one of the pipe joints 4.The next successive lower drill pipe section 3 is held against rotationby a conventional holding wrench (not shown). Referring to FIG. 3, thestop pin 35 is removed to allow the slide arm 7 to swing freely, and thehydraulic cylinder 30 is extended. Such extension of the cylinder 30causes the carriage 19 to move outwardly along the slide arm 7 to applya turning force to the wrench arm 26 in a wrenching movement around theupper drill pipe section 3. The threaded pipe joint 4 is thus broken, oruncoupled, efficiently and safely and usual drill pipe handlingapparatus may be employed to remove the drill pipe section from thedrill string.

The pivotal connection of the slide arm 7 and the sliding attachmentofthe wrench arm 26 eliminates the need for using a cable forpositioning a breakout wrench. The combination of elements also greatlyreduces the amount of manual handling incurred in the setup andoperation of a breakout mechanism. Accordingly, the possibility ofserious injury is lessened and safety in disjointing drill stringsections is improved. In addition, the movable carriage l9 and pivotablewrench arm 26 and jaws 29 coact to transmit a positive, centralizedwrenching movement for loosening the joints of a drill string.

We claim:

I. In a breakout wrench for grasping and turning sections of a drillstring of a drilling apparatus, the combination comprising:

a slide arm pivotally mounted at one end on the drilling apparatus whichswings in a plane substantially normal to a drill string of the drillingapparatus;

a carriage slidably mounted upon said slide arm for movement back andforth along said slide arm;

a hydraulic cylinder associated with said slide arm for pivotal movementtherewith, and having one end connected to said carriage for moving saidcarriage along said slide arm;

an elongate wrench arm pivoted to and extending from said carriage for aswinging movement relative to said slide arm in a plane substantiallyparalleling the plane of movement of said slide arm; and

a set of wrench jaws attached to the outer end of said wrench armadapted to close upon a section of a drill string to apply a wrenchingmovement thereto.

2. A breakout wrench as in claim 1, wherein said slide arm comprises anelongate cantilevered beam with a guide rail affixed to the underside ofthe outer portion of said beam, and said carriage hangs from and slidesalong said guide rail.

3. A breakout wrench as in claim 2, wherein said carriage has a baseplate underlying said guide rail and a pair of spaced, parallel slidesaffixed to said base plate that extend upward and turn over said guiderail to hang from and slide along said rail.

4. A breakout wrench as in claim 3, wherein said base plate of saidcarriage has a depending spindle portion about which said wrench armrotates, and the connecthat extends beneath said slide arm, and withsaid hydraulic cylinder disposed beneath said slide arm with one endconnected to said reaction plate.

6. In a breakout wrench for grasping and turning sections of a drillstring of a drilling apparatus having a mast framework, the combinationcomprising:

an elongated slide arm pivotably affixed at one end to the drillingapparatus and swingable towards and away from a drill string in a planesubstantially normal to the drill string;

a substantially upright pivot hinge securing the one end of said slidearm to the drilling apparatus;

a carriage having a trackway slidably engageable with said slide arm forlongitudinal movement therealong and a spindle portion disposed beneathsaid trackway;

a hydraulic cylinder associated with said slide for pivotal movementtherewith and having one end connected to said carriage for moving saidcarriage along said slide arm and another end attached to said pivothinge;

an elongate wrench arm disposed on and pivoted about said spindleportion for a swinging movement relative to said slide arm in a planesubstantially paralleling the plane of movement of said slide arm; and

a set of wrench jaws pivotably attached to the outer end of said wrencharm and adapted to grippingly engage and rotate a section of a drillstring.

7. A breakout wrench as recited in claim 6, wherein said wrench armincludes a curved outer end portion to which said wrench jaws areattached, an elongated shank portion extending horizontally from saidcurved outer end portion and a socket end connecting said shank portionwith said spindle portion for rotation thereabout.

1. In a breakout wrench for grasping and turning sections of a drillstring of a drilling apparatus, the combination comprising: a slide armpivotally mounted at one end on the drilling apparatus which swings in aplane substantially normal to a drill string of the drilling apparatus;a carriage slidably mounted upon said slide arm for movement back andforth along said slide arm; a hydraulic cylinder associated with saidslide arm for pivotal movement therewith, and having one end connectedto said carriage for moving said carriage along said slide arm; anelongate wrench arm pivoted to and extending from said carriage for aswinging movement relative to said slide arm in a plane substantiallyparalleling the plane of movement of said slide arm; and a set of wrenchjaws attached to the outer end of said wrench arm adapted to close upona section of a drill string to apply a wrenching movement thereto.
 2. Abreakout wrench as in claim 1, wherein said slide arm comprises anelongate cantilevered beam with a guide rail affixed to the underside ofthe outer portion of said beam, and said carriage hangs from and slidesalong said guide rail.
 3. A breakout wrench as in claim 2, wherein saidcarriage has a base plate underlying said guide rail and a pair ofspaced, parallel slides affixed to said base plate that extend upwardand turn over said guide rail to hang from and slide along said rail. 4.A breakout wrench as in claim 3, wherein said base plate of saidcarriage has a depending spindle portion about which said wrench armrOtates, and the connection of said slide arm with said hydrauliccylinder is with such spindle portion.
 5. A breakout wrench as recitedin claim 1 having a pivot hinge on the drilling apparatus which includesa substantially upright rotatable member, said slide arm being securedto said rotatable member, and there being a reaction plate secured tosaid rotatable member that extends beneath said slide arm, and with saidhydraulic cylinder disposed beneath said slide arm with one endconnected to said reaction plate.
 6. In a breakout wrench for graspingand turning sections of a drill string of a drilling apparatus having amast framework, the combination comprising: an elongated slide armpivotably affixed at one end to the drilling apparatus and swingabletowards and away from a drill string in a plane substantially normal tothe drill string; a substantially upright pivot hinge securing the oneend of said slide arm to the drilling apparatus; a carriage having atrackway slidably engageable with said slide arm for longitudinalmovement therealong and a spindle portion disposed beneath saidtrackway; a hydraulic cylinder associated with said slide for pivotalmovement therewith and having one end connected to said carriage formoving said carriage along said slide arm and another end attached tosaid pivot hinge; an elongate wrench arm disposed on and pivoted aboutsaid spindle portion for a swinging movement relative to said slide armin a plane substantially paralleling the plane of movement of said slidearm; and a set of wrench jaws pivotably attached to the outer end ofsaid wrench arm and adapted to grippingly engage and rotate a section ofa drill string.
 7. A breakout wrench as recited in claim 6, wherein saidwrench arm includes a curved outer end portion to which said wrench jawsare attached, an elongated shank portion extending horizontally fromsaid curved outer end portion and a socket end connecting said shankportion with said spindle portion for rotation thereabout.